I had the same problem with the pump but luckily I seem to have fixed it.

The pump fail because it tries to "suck" the door and after trying for some time, it quit sucking and time-out the pump. The #9 fuse trick merely reset it until it quits again.

What I did was that I disable the trunk pull-down entirely by removing the hose that does the pull down. The trunk have to be shut harder but that's fine for me as I can adjust the catch on both side to shut with as little effort as possible.

It seems with one of the hose removed, (can't remeber which one but I am sure you can try) all 4 doors seems to have the close-assist function working very well. I have not been resetting my pump for 3 months.

I also figured that with the plastic cushion housing the pump removed, the pump would work fine as it breath much better. This will be my next bet if the pump fail on me.

I am happy that I fixed this little one so far as the pump isn't really broken down. Just a bit inefficient and the computer time-out the bugger!

Give it a try before forking our $$$